Strongly-Confined CsPbBr3 Perovskite Quantum Dots with Ultralow Trap Density and Narrow Size Distribution for Efficient Pure-Blue Light-Emitting Diodes.

The development of pure-blue perovskite light-emitting diodes (PeLEDs) faces challenges of spectral stability and low external quantum efficiency (EQE) due to phase separation in mixed halide compositions. Perovskite quantum dots (QDs) with strong confinement effects are promising alternatives to achieve high-quality pure-blue PeLEDs, yet their performance is often hindered by the poor size distribution and high trap density. A strategy combining thermodynamic control with a polishing-driven ligand exchange process to produce high-quality QDs is developed. The strongly-confined pure-blue (≈470 nm) CsPbBr3 QDs exhibit narrow size distribution (12% dispersion) and are achieved in Br-rich ion environment based on growth thermodynamic control. Subsequent polishing-driven ligand exchange process removes imperfect surface sites and replaces initial long-chain organic ligands with short-chain benzene ligands. The resulting QDs exhibit high photoluminescence quantum yield (PLQY) to near-unity. The resulting PeLEDs exhibit a pure-blue electroluminescence (EL) emission at 472 nm with narrow full-width at half-maximum (FWHM) of 25 nm, achieving a maximum EQE of 10.7% and a bright maximum luminance of 7697 cd m-2. The pure-blue PeLEDs show ultrahigh spectral stability under high voltage, a low roll-off of EQE, and an operational half-lifetime (T50) of 127 min at an initial luminance of 103 cd m-2 under continuous operation.

Inhibition of TLR signaling by a bacterial protein containing immunoreceptor tyrosine-based inhibitory motifs.

The protein Tir (translocated intimin receptor) in enteric bacteria shares sequence similarity with the host cellular immunoreceptor tyrosine-based inhibition motifs (ITIMs). Despite the importance of Tir in pedestal formation, relatively little is known about the role of Tir and its ITIMs in the regulation of the host immune response. Here we demonstrate that Tir from enteropathogenic Escherichia coli (EPEC) interacted with the host cellular tyrosine phosphatase SHP-1 in an ITIM phosphorylation-dependent manner. The association of Tir with SHP-1 facilitated the recruitment of SHP-1 to the adaptor TRAF6 and inhibited the ubiquitination of TRAF6. Moreover, the ITIMs of Tir suppressed EPEC-stimulated expression of proinflammatory cytokines and inhibited intestinal immunity to infection with Citrobacter rodentium. Our findings identify a previously unknown mechanism by which bacterial ITIM-containing proteins can inhibit innate immune responses.

Pre-morbid sleep disturbance and its association with stroke severity: results from the international INTERSTROKE study.

BACKGROUND AND PURPOSE: Whilst sleep disturbances are associated with stroke, their association with stroke severity is less certain. In the INTERSTROKE study, the association of pre-morbid sleep disturbance with stroke severity and functional outcome following stroke was evaluated. METHODS: INTERSTROKE is an international case-control study of first acute stroke. This analysis included cases who completed a standardized questionnaire concerning nine symptoms of sleep disturbance (sleep onset latency, duration, quality, nocturnal awakening, napping duration, whether a nap was planned, snoring, snorting and breathing cessation) in the month prior to stroke (n = 2361). Two indices were derived representing sleep disturbance (range 0-9) and obstructive sleep apnoea (range 0-3) symptoms. Logistic regression was used to estimate the magnitude of association between symptoms and stroke severity defined by the modified Rankin Score. RESULTS: The mean age of participants was 62.9 years, and 42% were female. On multivariable analysis, there was a graded association between increasing number of sleep disturbance symptoms and initially severe stroke (2-3, odds ratio [OR] 1.44, 95% confidence interval [CI] 1.07-1.94; 4-5, OR 1.66, 95% CI 1.23-2.25; >5, OR 2.58, 95% CI 1.83-3.66). Having >5 sleep disturbance symptoms was associated with significantly increased odds of functional deterioration at 1 month (OR 1.54, 95% CI 1.01-2.34). A higher obstructive sleep apnoea score was also associated with significantly increased odds of initially severe stroke (2-3, OR 1.48; 95% CI 1.20-1.83) but not functional deterioration at 1 month (OR 1.19, 95% CI 0.93-1.52). CONCLUSIONS: Sleep disturbance symptoms were common and associated with an increased odds of severe stroke and functional deterioration. Interventions to modify sleep disturbance may help prevent disabling stroke/improve functional outcomes and should be the subject of future research.

Blood pressure variability in acute stroke: Risk factors and association with functional outcomes at 1 month.

BACKGROUND AND PURPOSE: Blood pressure variability, in acute stroke, may be an important modifiable determinant of functional outcome after stroke. In a large international cohort of participants with acute stroke, it was sought to determine the association of blood pressure variability (in the early period of admission) and functional outcomes, and to explore risk factors for increased blood pressure variability. PATIENTS AND METHODS: INTERSTROKE is an international case-control study of risk factors for first acute stroke. Blood pressure was recorded at the time of admission, the morning after admission and the time of interview in cases (median time from admission 36.7 h). Multivariable ordinal regression analysis was employed to determine the association of blood pressure variability (standard deviation [SD] and coefficient of variance) with modified Rankin score at 1-month follow-up, and logistic regression was used to identify risk factors for blood pressure variability. RESULTS: Amongst 13,206 participants, the mean age was 62.19 ± 13.58 years. When measured by SD, both systolic blood pressure variability (odds ratio 1.13; 95% confidence interval 1.03-1.24 for SD ≥20 mmHg) and diastolic blood pressure variability (odds ratio 1.15; 95% confidence interval 1.04-1.26 for SD ≥10 mmHg) were associated with a significant increase in the odds of poor functional outcome. The highest coefficient of variance category was not associated with a significant increase in risk of higher modified Rankin score at 1 month. Increasing age, female sex, high body mass index, history of hypertension, alcohol use, and high urinary potassium and low urinary sodium excretion were associated with increased blood pressure variability. CONCLUSION: Increased blood pressure variability in acute stroke, measured by SD, is associated with an increased risk of poor functional outcome at 1 month. Potentially modifiable risk factors for increased blood pressure variability include low urinary sodium excretion.

On-site analysis and rapid identification of citrus herbs by miniature mass spectrometry and machine learning.

BACKGROUND: Natural medicines present a considerable analytical challenge due to their diverse botanical origins and complex multi-species composition. This inherent complexity complicates their rapid identification and analysis. Tangerine peel, a product of the Citrus species from the Rutaceae family, is widely used both as a culinary ingredient and in traditional Chinese medicine. It is classified into two primary types in China: Citri Reticulatae Pericarpium (CP) and Citri Reticulatae Pericarpium Viride (QP), differentiated by harvest time. A notable price disparity exists between CP and another variety, Citri reticulatae "Chachi" (GCP), with differences being based on the original variety. METHODS: This study introduces an innovative method using portable miniature mass spectrometry for swift on-site analysis of QP, CP, and GCP, requiring less than a minute per sample. And combined with machine learning to differentiate the three types on site, the method was used to try to distinguish GCP from different storage years. RESULTS: This novel method using portable miniature mass spectrometry for swift on-site analysis of tangerine peels enabled the characterization of 22 compounds in less than one minute per sample. The method simplifies sample processing and integrates machine learning to distinguish between the CP, QP, and GCP varieties. Moreover, a multiple-perceptron neural network model is further employed to specifically differentiate between CP and GCP, addressing the significant price gap between them. CONCLUSIONS: The entire analytical time of the method is about 1 minute, and samples can be analyzed on site, greatly reducing the cost of testing. Besides, this approach is versatile, operates independently of location and environmental conditions, and offers a valuable tool for assessing the quality of natural medicines.

Rapid analysis of bioactive compounds from citrus samples by direct analysis in real-time mass spectrometry combined with chemometrics.

Renowned for their nutritional benefits, citrus fruits are harvested at various stages in China for functional food production. This study introduces an innovative analytical method, DART-MS, enabling direct qualitative analysis of citrus samples without the need for preprocessing. Simultaneously, the combination of chemometrics can be applied to distinguish between three different citrus samples: Citri Reticulatae Pericarpium, Citri Reticulatae Pericarpium Viride, and Citri Reticulatae "Chachi". Notably, given the international regulatory concerns surrounding synephrine, a precise quantitative analysis method for synephrine was developed. The limit of detection (LOD) and the limit of quantification (LOQ) were 39 ng mL-1 and 156 ng mL-1, respectively. The recovery rates obtained varied from 98.46% to 100.71%. Furthermore, the intra-day and inter-day precision demonstrated robust consistency, with values spanning 5.0-6.1% and 5.03-6.08%, respectively, offering quicker results compared to those from HPLC-MS, promising a safer assessment of herbal and food products.

FragGrow: A Web Server for Structure-Based Drug Design by Fragment Growing within Constraints.

Fragment growing is an important ligand design strategy in drug discovery. In this study, we present FragGrow, a web server that facilitates structure-based drug design by fragment growing. FragGrow offers two working modes: one for growing molecules through the direct replacement of hydrogen atoms or substructures and the other for growing via virtual synthesis. FragGrow works by searching for suitable fragments that meet a set of constraints from an indexed 3D fragment database and using them to create new compounds in 3D space. The users can set a range of constraints when searching for their desired fragment, including the fragment's ability to interact with specific protein sites; its size, topology, and physicochemical properties; and the presence of particular heteroatoms and functional groups within the fragment. We hope that FragGrow will serve as a useful tool for medicinal chemists in ligand design. The FragGrow server is freely available to researchers and can be accessed at https://fraggrow.xundrug.cn.

Acceptability and experience of a smartphone symptom monitoring app for people with psychosis in China (YouXin): a qualitative study.

BACKGROUND: Access to high-quality mental healthcare remains challenging for people with psychosis globally, including China. Smartphone-based symptom monitoring has the potential to support scalable mental healthcare. However, no such tool, until now, has been developed and evaluated for people with psychosis in China. This study investigated the acceptability and the experience of using a symptom self-monitoring smartphone app (YouXin) specifically developed for people with psychosis in China. METHODS: Semi-structured interviews were conducted with 10 participants with psychosis to explore the acceptability of YouXin. Participants were recruited from the non-randomised feasibility study that tested the validity, feasibility, acceptability and safety of the YouXin app. Data analysis was guided by the theoretical framework of acceptability. RESULTS: Most participants felt the app was acceptable and easy to use, and no unbearable burdens or opportunity costs were reported. Participants found completing the self-monitoring app rewarding and experienced a sense of achievement. Privacy and data security were not major concerns for participants, largely due to trust in their treating hospital around data protection. Participants found the app easy to use and attributed this to the training provided at the beginning of the study. A few participants said they had built some form of relationship with the app and would miss the app when the study finished. CONCLUSIONS: The YouXin app is acceptable for symptom self-monitoring in people with experience of psychosis in China. Participants gained greater insights about their symptoms by using the YouXin app. As we only collected retrospective acceptability in this study, future studies are warranted to assess hypothetical acceptability before the commencement of study to provide a more comprehensive understanding of implementation.

Cation doping and oxygen vacancies in the orthorhombic FeNbO4 material for solid oxide fuel cell applications: A density functional theory study.

The orthorhombic phase of FeNbO4, a promising anode material for solid oxide fuel cells (SOFCs), exhibits good catalytic activity toward hydrogen oxidation. However, the low electronic conductivity of the material specifically in the pure structure without defects or dopants limits its practical applications as an SOFC anode. In this study, we have employed density functional theory (DFT + U) calculations to explore the bulk and electronic properties of two types of doped structures, Fe0.9375A0.0625NbO4 and FeNb0.9375B0.0625O4 (A, B = Ti, V, Cr, Mn, Co, Ni) and the oxygen-deficient structures Fe0.9375A0.0625NbO3.9375 and FeNb0.9375B0.0625O3.9375, where the dopant is positioned in the first nearest neighbor site to the oxygen vacancy. Our DFT simulations have revealed that doping in the Fe sites is energetically favorable compared to doping in the Nb site, resulting in significant volume expansion. The doping process generally requires less energy when the O-vacancy is surrounded by one Fe and two Nb ions. The simulated projected density of states of the oxygen-deficient structures indicates that doping in the Fe site, particularly with Ti and V, considerably narrows the bandgap to ∼0.5 eV, whereas doping with Co at the Nb sites generates acceptor levels close to 0 eV. Both doping schemes, therefore, enhance electron conduction during SOFC operation.

The role of mitochondrial dynamics and mitophagy in skeletal muscle atrophy: from molecular mechanisms to therapeutic insights.

Skeletal muscle is the largest metabolic organ of the human body. Maintaining the best quality control and functional integrity of mitochondria is essential for the health of skeletal muscle. However, mitochondrial dysfunction characterized by mitochondrial dynamic imbalance and mitophagy disruption can lead to varying degrees of muscle atrophy, but the underlying mechanism of action is still unclear. Although mitochondrial dynamics and mitophagy are two different mitochondrial quality control mechanisms, a large amount of evidence has indicated that they are interrelated and mutually regulated. The former maintains the balance of the mitochondrial network, eliminates damaged or aged mitochondria, and enables cells to survive normally. The latter degrades damaged or aged mitochondria through the lysosomal pathway, ensuring cellular functional health and metabolic homeostasis. Skeletal muscle atrophy is considered an urgent global health issue. Understanding and gaining knowledge about muscle atrophy caused by mitochondrial dysfunction, particularly focusing on mitochondrial dynamics and mitochondrial autophagy, can greatly contribute to the prevention and treatment of muscle atrophy. In this review, we critically summarize the recent research progress on mitochondrial dynamics and mitophagy in skeletal muscle atrophy, and expound on the intrinsic molecular mechanism of skeletal muscle atrophy caused by mitochondrial dynamics and mitophagy. Importantly, we emphasize the potential of targeting mitochondrial dynamics and mitophagy as therapeutic strategies for the prevention and treatment of muscle atrophy, including pharmacological treatment and exercise therapy, and summarize effective methods for the treatment of skeletal muscle atrophy.

A pair of dopamine neurons mediate chronic stress signals to induce learning deficit in Drosophila melanogaster.

Chronic stress could induce severe cognitive impairments. Despite extensive investigations in mammalian models, the underlying mechanisms remain obscure. Here, we show that chronic stress could induce dramatic learning and memory deficits in Drosophila melanogaster The chronic stress-induced learning deficit (CSLD) is long lasting and associated with other depression-like behaviors. We demonstrated that excessive dopaminergic activity provokes susceptibility to CSLD. Remarkably, a pair of PPL1-γ1pedc dopaminergic neurons that project to the mushroom body (MB) γ1pedc compartment play a key role in regulating susceptibility to CSLD so that stress-induced PPL1-γ1pedc hyperactivity facilitates the development of CSLD. Consistently, the mushroom body output neurons (MBON) of the γ1pedc compartment, MBON-γ1pedc>α/ß neurons, are important for modulating susceptibility to CSLD. Imaging studies showed that dopaminergic activity is necessary to provoke the development of chronic stress-induced maladaptations in the MB network. Together, our data support that PPL1-γ1pedc mediates chronic stress signals to drive allostatic maladaptations in the MB network that lead to CSLD.

A Novel Zero-Velocity Interval Detection Algorithm for a Pedestrian Navigation System with Foot-Mounted Inertial Sensors.

The zero-velocity update (ZUPT) algorithm is a pivotal advancement in pedestrian navigation accuracy, utilizing foot-mounted inertial sensors. Its key issue hinges on accurately identifying periods of zero-velocity during human movement. This paper introduces an innovative adaptive sliding window technique, leveraging the Fourier Transform to precisely isolate the pedestrian's gait frequency from spectral data. Building on this, the algorithm adaptively adjusts the zero-velocity detection threshold in accordance with the identified gait frequency. This adaptation significantly refines the accuracy in detecting zero-velocity intervals. Experimental evaluations reveal that this method outperforms traditional fixed-threshold approaches by enhancing precision and minimizing false positives. Experiments on single-step estimation show the adaptability of the algorithm to motion states such as slow, fast, and running. Additionally, the paper demonstrates pedestrian trajectory localization experiments under a variety of walking conditions. These tests confirm that the proposed method substantially improves the performance of the ZUPT algorithm, highlighting its potential for pedestrian navigation systems.

Markers of periodontal disease and risk of stroke: INTERSTROKE case-control study.

BACKGROUND: Periodontal disease may be an important modifiable risk factor for stroke. AIMS: To determine the contribution of markers of periodontal disease to stroke risk globally, within subpopulations, and by stroke subtypes. METHODS: INTERSTROKE is the largest international case-control study of risk factors for first acute stroke. All participants were asked a standardised set of questions about the presence or absence of painful teeth, painful gums or lost teeth, as markers of periodontal disease, within the previous year. The total number of reported variables was calculated per participant. Multivariable conditional logistic regression examined the association of these variables with acute stroke. RESULTS: In 26901 participants, across 32 countries, there was a significant multivariable association between lost teeth and stroke (OR 1.11, 95 % CI 1.01 - 1.22), but not painful teeth (OR 1.00, 95 % CI 0.91-1.10) or painful gums (OR 1.01, 95 % CI 0.89 - 1.14). When these symptoms were considered together there was a graded increased odds of stroke, with the largest magnitude of association seen if a patient reported all three of painful teeth, painful gums and lost teeth (OR 1.34, 95 % CI 1.00 - 1.79). CONCLUSIONS: Our findings suggest that features of severe periodontal disease are a risk factor for acute stroke. Periodontal disease should be considered as a potentially modifiable risk factor for stroke.

Effect of transcutaneous electrical nerve stimulation (TENS) on the electromyographic activity of human masticatory muscles in young people with normal occlusion.

STATEMENT OF PROBLEM: Transcutaneous electrical nerve stimulation (TENS) has been used in several clinical areas. However, the effect of TENS on the masticatory muscles of young individuals with normal occlusion remains unclear. PURPOSE: The purpose of the study was to assess the effect of TENS on the surface electromyographic (sEMG) activity of masticatory muscles in a young population with normal occlusion. MATERIAL AND METHODS: Twenty residents (5 men and 15 women, mean 24.27 ±2.59 years) of Dalian Stomatological Hospital were enrolled as the study participants. A trained operator collected the required information from the participants. The experiment was divided into 3 stages: pre-TENS acquisition, TENS application, and post-TENS acquisition. The pre-TENS stage was performed using surface electromyography (sEMG) (Myotronics Inc) to acquire the potential values of masticatory muscles in the following 3 states 5 times each: resting, intercuspal occlusion (ICO), and maximum voluntary clench (clenching). The potential values of the anterior of temporalis (TA), the masseter (MM), the sternocleidomastoid (SCM), and the anterior digastric (DA) muscles were collected in the resting state, and TA and MM were collected in the ICO and clenching states. During the TENS application phase, a TENS Unit device (J5 Myomonitor) (J5) was used on each participant for 45 minutes. The post-TENS acquisition phase involved the same procedure as the pre-TENS phase. The experimental data were recorded, and the normality of each group was analyzed using the Shapiro-Wilk test in a statistical software program (IBM SPSS Statistics, v26.0). The paired-sample t test was used to compare the differences in the mean values of sEMG and the asymmetry index (As); the independent-sample t test was used to compare the activity index (Ac) and torque index (To) (α=.05). RESULTS: Significant differences were observed in the mean potential values of TA, MM, LSCM, and RDA before and after TENS in the resting state and RTA, LMM, and RMM before and after TENS in the clenching state (P<.05). Moreover, although AsDA values showed a significant difference (P=.027) before and after TENS in the resting state, the differences in As values for the other muscles in the resting state were statistically similar. Furthermore, in each state, the mean values of Ac and To after TENS showed no significant differences before and after TENS (P>.05). CONCLUSIONS: The resting EMG values of the TA and MM differed significantly before and after TENS. After TENS, the resting EMG activity decreased, whereas the functional EMG activity tended to increase.

BTA2 regulates tiller angle and the shoot gravity response through controlling auxin content and distribution in rice.

Tiller angle is a key agricultural trait that establishes plant architecture, which in turn strongly affects grain yield by influencing planting density in rice. The shoot gravity response plays a crucial role in the regulation of tiller angle in rice, but the underlying molecular mechanism is largely unknown. Here, we report the identification of the BIG TILLER ANGLE2 (BTA2), which regulates tiller angle by controlling the shoot gravity response in rice. Loss-of-function mutation of BTA2 dramatically reduced auxin content and affected auxin distribution in rice shoot base, leading to impaired gravitropism and therefore a big tiller angle. BTA2 interacted with AUXIN RESPONSE FACTOR7 (ARF7) to modulate rice tiller angle through the gravity signaling pathway. The BTA2 protein was highly conserved during evolution. Sequence variation in the BTA2 promoter of indica cultivars harboring a less expressed BTA2 allele caused lower BTA2 expression in shoot base and thus wide tiller angle during rice domestication. Overexpression of BTA2 significantly increased grain yield in the elite rice cultivar Huanghuazhan under appropriate dense planting conditions. Our findings thus uncovered the BTA2-ARF7 module that regulates tiller angle by mediating the shoot gravity response. Our work offers a target for genetic manipulation of plant architecture and valuable information for crop improvement by producing the ideal plant type.

Integrated single-molecule real-time sequencing and RNA sequencing reveal the molecular mechanisms of salt tolerance in a novel synthesized polyploid genetic bridge between maize and its wild relatives.

BACKGROUND: Tripsacum dactyloides (2n = 4x = 72) and Zea perennis (2n = 4x = 40) are tertiary gene pools of Zea mays L. and exhibit many abiotic adaptations absent in modern maize, especially salt tolerance. A previously reported allopolyploid (hereafter referred to as MTP, 2n = 74) synthesized using Zea mays, Tripsacum dactyloides, and Zea perennis has even stronger salt tolerance than Z. perennis and T. dactyloides. This allopolyploid will be a powerful genetic bridge for the genetic improvement of maize. However, the molecular mechanisms underlying its salt tolerance, as well as the key genes involved in regulating its salt tolerance, remain unclear. RESULTS: Single-molecule real-time sequencing and RNA sequencing were used to identify the genes involved in salt tolerance and reveal the underlying molecular mechanisms. Based on the SMRT-seq results, we obtained 227,375 reference unigenes with an average length of 2300 bp; most of the unigenes were annotated to Z. mays sequences (76.5%) in the NR database. Moreover, a total of 484 and 1053 differentially expressed genes (DEGs) were identified in the leaves and roots, respectively. Functional enrichment analysis of DEGs revealed that multiple pathways responded to salt stress, including "Flavonoid biosynthesis," "Oxidoreductase activity," and "Plant hormone signal transduction" in the leaves and roots, and "Iron ion binding," "Acetyl-CoA carboxylase activity," and "Serine-type carboxypeptidase activity" in the roots. Transcription factors, such as those in the WRKY, B3-ARF, and bHLH families, and cytokinin negatively regulators negatively regulated the salt stress response. According to the results of the short time series-expression miner analysis, proteins involved in "Spliceosome" and "MAPK signal pathway" dynamically responded to salt stress as salinity changed. Protein-protein interaction analysis revealed that heat shock proteins play a role in the large interaction network regulating salt tolerance. CONCLUSIONS: Our results reveal the molecular mechanism underlying the regulation of MTP in the response to salt stress and abundant salt-tolerance-related unigenes. These findings will aid the retrieval of lost alleles in modern maize and provide a new approach for using T. dactyloides and Z. perennis to improve maize.

Hydrophobic Carbon Dots Derived from Organic Pollutants and Applications in NIR Anticounterfeiting and Bioimaging.

In an effort to fulfill the strategy of sustainable development, Rhodamine B, a common and toxic organic pollutant in the textile industry, was reported for the first time as a single precursor to develop a kind of novel hydrophobic nitrogen-doped carbon dot (HNCD) through a green and facile one-pot solvothermal method. The HNCDs with an average size of 3.6 nm possess left and right water contact angles of 109.56° and 110.34°, respectively. The HNCDs manifest excitation wavelength-tunable and upconverted fluorescence from the ultraviolet (UV) to the near-infrared (NIR) range. Furthermore, the PEGylation of HNCDs enables them to be used as an optical marker for cell and in vivo imaging. Notably, the HNCDs with solvent-dependent fluorescence can be used for invisible inks with a wide range of light responses from UV-vis-NIR spectra. This work not only provides an innovative way to recycle chemical waste but also expands the potential application of HNCDs in NIR security printing and bioimaging.

Eggshell spots are an important cue for the egg retrieval behavior in two tit species.

It is a common occurrence for incubating female ground- or cavity-nesting birds to accidentally roll their own eggs out of the nest cup. To correctly roll eggs that are not in the nest cup back to the nest, birds must be able to discriminate between their eggs and things around their nests that could be easily confused for their eggs (e.g., egg-shaped stones or other birds' eggs). Moreover, there may be a strong interaction between egg retrieval and egg rejection behaviors in the context of avian brood parasitism where recognition and rejection of alien eggs is an effective means for hosts to defend against cuckoo parasitism. It has been shown that green-backed tits (Parus monticolus) and Japanese tits (P. minor) in China have strong egg recognition ability and are able to reject nonmimetic eggs in the nest. Eggshell spots play an essential role in the egg rejection behavior of these two tit hosts. This study investigated the egg retrieval behavior of green-backed tits and Japanese tits by adding one experimental egg to the nest corner to explore whether eggshell spots also play a role in the process of egg retrieval. The results revealed significant differences in the retrieval rates of white-rumped munia (Lonchura striata) eggs painted with spots, Japanese tits' own true eggs, and unpainted, pure white-white-rumped munia eggs. The retrieval rate of white-white-rumped munia eggs was significantly lower than that of spotted white-rumped munia eggs and Japanese tits' own spotted eggs. For green-backed tits, the retrieval rate of spotted white-rumped munia eggs in the nest corner was significantly higher than that of pure white-white-rumped munia eggs, while the rejection rate of spotted white-rumped munia eggs was significantly lower than that of pure white-white-rumped munia eggs. These findings indicate that eggshell spots play a key role in the egg retrieval of green-backed tits and Japanese tits.

Synthesis of pendant fullerene dimers by an aminomethylation reaction of fulleropyrrolidines bearing ketone moieties.

An aminomethylation reaction of fulleropyrrolidines bearing ketone moieties in the presence of N-unsubstituted fulleropyrrolidines and paraformaldehyde with the aid of p-toluenesulfonic acid afforded a series of scarce pendant fullerene dimers. A simple change of reaction substrates from ketone to ketone-containing fulleropyrrolidines successfully realized the synthesis of a variety of novel pendant fullerene dimers, including those from methyl ketone-containing fulleropyrrolidines, which were considered to produce the known bridged fullerene dimers. It should be noted that pendant fullerene dimers are usually difficult to prepare by other methods and may have promising applications in perovskite solar cells. Density functional theory (DFT) has been employed to elucidate the regioselectivity of methyl ketone-containing fulleropyrrolidines to yield exclusively pendant fullerene dimers by investigating the Gibbs free energy profile of the reaction starting from methyl ketone-containing fulleropyrrolidines and iminium intermediates.

MolTaut: A Tool for the Rapid Generation of Favorable Tautomer in Aqueous Solution.

Fast and proper treatment of the tautomeric states for drug-like molecules is critical in computer-aided drug discovery since the major tautomer of a molecule determines its pharmacophore features and physical properties. We present MolTaut, a tool for the rapid generation of favorable states of drug-like molecules in water. MolTaut works by enumerating possible tautomeric states with tautomeric transformation rules, ranking tautomers with their relative internal energies and solvation energies calculated by AI-based models, and generating preferred ionization states according to predicted microscopic pKa. Our test shows that the ranking ability of the AI-based tautomer scoring approach is comparable to the DFT method (wB97X/6-31G*//M062X/6-31G*/SMD) from which the AI models try to learn. We find that the substitution effect on tautomeric equilibrium is well predicted by MolTaut, which is helpful in computer-aided ligand design. The source code of MolTaut is freely available to researchers and can be accessed at https://github.com/xundrug/moltaut. To facilitate the usage of MolTaut by medicinal chemists, we made a free web server, which is available at http://moltaut.xundrug.cn. MolTaut is a handy tool for investigating the tautomerization issue in drug discovery.